6 Replies Latest reply on May 30, 2016 2:34 PM by romainc92869029

    3D camera tracking on lower resolution


      Hello !

      First thank you for this wonderful software : )

      I'm a beginner.


      When I apply the 3D camera tracker to a 3 minutes 1080p video - handheld shot, so a bit shaky - in my example i shot a simple soccer goal-frame without moving too much, 2 steps or so, around my initial position, note that the background consists of trees and plants with some wind,

      on my new laptop (quad core i7, 16GB of ram),

      the computation is very long (about 45min) and gets stuck on "Camera solving".


      When I apply the tracker on a 1 minute extract, it's about 15minutes of calculation and it works.


      My question : because in the near future i want to apply this tracker on longer videos (about 5 minutes or more), i'm looking for a method that could get it work !

      Is it realistic to you ?


      Here's a small thing I tried : I used Handbrake to output a lower resolution of the original video (700p width), and applied the tracker on it.

      It worked and the calculation is faster. I derived a solid from some tracked points I chose. It works well in this 700p video.


      But, from this, how could i get this solid well in the original 1080p video ? I tried to copy&paste the solid in the 1080p video but the tracking isnot good anymore.


      Thank you very much, your help is much appreciated : )


        • 1. Re: 3D camera tracking on lower resolution
          Rick Gerard Adobe Community Professional & MVP

          Your newness is showing. Try this next time you watch a movie or a tv show. Count the number of seconds between cuts. 90% of everything I work on in After Effects is under 10 seconds. Sticking on a single shot for 5 minutes will loose your audience.


          What you want to do is pre-edit your stuff and only process the shots you are going to actually use.


          Now to the Camera Tracker. It's an insane resource hog and a five minute camera track would be very difficult to do with any software. You can't really camera track a smaller version (smaller frame size) and have things work out in a larger comp. You can't really camera track a low resolution proxy because all of the good detail that you want to track is going to be lost so the track will not be as good.


          Also, and this is a can't bust it rule. All shots will not Camera Track. You have to have a fair amount of fixed geometry in the scene and you may have to eliminate a bunch of the trackers if there is a lot of other motion going on in the scene. If you want good camera tracking you will have to very carefully plan your shots to guarantee that they can be tracked.


          One more time... it's nuts to try and run a camera track on a five minute shot unless you think you absolutely have to use the entire five minute shot in your movie. If you have to you'll have to be extra careful.  If you are camera tracking to insert 3D objects in the scene then you only need to camera track the part of the shot where the 3D objects are going to be in frame. IOW, walk down the sidewalk for five minutes and pass a store that you want to change a sign in. You pass the area of the sign for 7 seconds so you cut the shot up and only camera track the 7 seconds you need.

          • 2. Re: 3D camera tracking on lower resolution
            romainc92869029 Level 1

            Thank you Rick. It's very helpful.

            The goal is to make educational videos : i want to embed some Math in clearly defined planes found outside, a wall, a brick, a path ...

            The plane plays the role of the blackboard ! I know it sounds a bit weird, but this is what i want to do.

            Because it's educational, the plane has to be tracked during some minutes, not seconds, so that i can explain things.


            Would you have an idea about how i could achieve this ?


            So plan my shots, and maybe cut the original video into small pieces that can be tracked more easily ... Ok


            Given the goal, would you advise me to use the perspective corner pin tracking ?

            • 3. Re: 3D camera tracking on lower resolution
              Rick Gerard Adobe Community Professional & MVP

              The kind of tracking you use depends on the shot. The shot you set up depends on the story you are trying to tell and where you want the eyes to focus. To be effective you need to consider the story you are telling, the way color movement and composition enhance the story or detract from it's telling. If it was my assignment to explain the Pythagorean theorem I would start by looking at something like this illustration:


              Then I would figure out what I could shoot to tell that story in effective ways and start figuring out how to break up the explanation into interesting parts. I would not fixate on one plane for a five minute explanation of the whole thing. I'd look for a triangle. Maybe walk around a playground in a park and look for triangles that I could find and outline them with some kind of sketch while the voice over said something like "There are triangles all around us" and the video showed two or three or maybe four triangles. For maybe each couple of sentences that were used to explain what you were trying to explain I would have a graphic illustrated how to square a value, then show how to figure out what a right angle is, then use another graphic to show how adding the square of two values gives you a bigger box and if you merge those boxes into a new square the length of the side is going to be equal to . . .


              You get the idea. Cut up the graphics ant text that use to match the explanation and edit between them. Even if you wanted to stick with one shot, there would be places you could cut or transition from one graphic to another. In the end you could then put up the whole graphic or make it come together. That would be interesting. Just finding something on your walk that would be big enough to be a chalk board for your explanation and trying to do the full five minute explanation of how to do the math would not hold the audience. The chalkboard on the wall would be a gimmick and quickly be as boring as the chalkboard in the classroom.


              I've done similar things. One was a safety film for a paper company where we walked through the factory with a stedicam and laid dolly track to get the shots we needed. Big, professional gear was required then to get smooth shots. (not an image from my production)

              Screen Shot 2016-05-28 at 7.07.06 AM.png

              We used the right gear to get the steadiest shots we could so you could stand to watch the moving shots and concentrate on the message. We said things like if you put your hand here it will suck you into the paper machine and we'll have to stop the machine, throw away a bunch of paper and see if we can find your body.... We made the point. Today, for about $500 you can pick up a 3 axis stabilizer for a GoPro or a Smart Phone or a small camera. If you are going to produce this kind of video I strongly recommend that you invest in some kind of stabilizing equipment. Then carefully script your presentation and figure out the best way you can visually tell your story. I like the idea of drawing on surfaces you find while walking around. I've been doing that for about 40 years.

              • 4. Re: 3D camera tracking on lower resolution
                romainc92869029 Level 1

                Thank you very much Rick,

                your answer made me rethink the whole thing.

                The goal is indeed to catch the attention, i'm gonna work on all this.

                As for the stabilizing equipment, i understand, but i'd like to keep spontaneity.

                • 5. Re: 3D camera tracking on lower resolution
                  Rick Gerard Adobe Community Professional & MVP

                  There is nothin less spontaneous than trying to watch poorly shot hand held footage. I have been shooting hand held for more than 40 years and was once considered one of the best hand held camera operators in the country because mr hand held footage was amazingly stable and the viewer was never distracted from the message by bad camera work. I would never attempt to hand hold a shot with a normal lense using a camera weying less than 5 to 7 pounds, especially if the camera was not specificly designed for hand held cinematography. Think DSLR.


                  A DGI Osmo (DJIOsmo - Specifications, FAQ, videos tutorials, manuals, DJI GO | DJI ) would make you look like a genius with a few days practice and give you smooth enough hand held footage that you could focus the attention on some added and tracked graphics. It cost less than a good semi pro DSLR and is much more suited to your project.


                  Shoot it on a consumer camera withoit a lot of practice and you will spend a lot of time the Warp stabilizer fixing shots and rendering intermediates to get something watchable. I just trying to help you make a product that someone would want to watch or buy.

                  • 6. Re: 3D camera tracking on lower resolution
                    romainc92869029 Level 1

                    Thank you very much ! I did not know this amazing product.

                    I have to WORK now : )

                    Really, thanks again, you made me rethink the whole concept. I'm making videos everyday for my business, but it's not the only thing i'm doing so i'll improve ... I'd like to show you one of the videos, in a few weeks, i hope i won't disappoint you ^^